package com.atguigu.gulimall.cart.interceptor;

import com.atguigu.common.constant.AuthServerConstant;
import com.atguigu.common.constant.CartConstant;
import com.atguigu.common.vo.MemberRespVo;
import com.atguigu.gulimall.cart.vo.UserInfoTo;
import org.apache.commons.lang.StringUtils;
import org.springframework.stereotype.Component;
import org.springframework.web.servlet.HandlerInterceptor;
import org.springframework.web.servlet.ModelAndView;

import javax.servlet.http.Cookie;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
import java.util.UUID;

/**
 * 拦截器，在执行目标方法之前，判断用户的登录状态，并封装传递给controller目标请求
 */
public class CartInterceptor implements HandlerInterceptor {

    public static ThreadLocal<UserInfoTo> threadLocal = new ThreadLocal<>();

    /**
     * 在目标方法执行之前
     * @param request
     * @param response
     * @param handler
     * @return
     * @throws Exception
     */
    @Override
    public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {
        UserInfoTo userInfoTo = new UserInfoTo();
        HttpSession session = request.getSession();
        MemberRespVo member = (MemberRespVo) session.getAttribute(AuthServerConstant.LOGIN_USER);//获取当前登录的用户
        System.out.println(member);
        if (member != null) {  //说明用户登录了
            userInfoTo.setUserId(member.getId());
        }
        Cookie[] cookies = request.getCookies();  //获取cookies里的数据
        if (cookies != null && cookies.length>0) {
            for (Cookie cookie : cookies) {  //遍历cookies
                String name = cookie.getName();  //获取cookie的名字
                if (name.equals(CartConstant.TEMP_USER_COOKIE_NAME)) { //判断当前cookie的名字是否等于我们指定的cookie的名字
                    //说明拿到cookie了
                    userInfoTo.setUserKey(cookie.getValue());
                    userInfoTo.setTempUser(true);
                }
            }

        }
        //如果没有临时用户一定分配一个临时用户
        if (StringUtils.isEmpty(userInfoTo.getUserKey())) {  //判断临时用户是否为空
            //没有临时用户
            String uuid = UUID.randomUUID().toString();  //生成一个uuid
        }
        threadLocal.set(userInfoTo);  //在目标方法执行之前
        return true;
    }

    /**
     * 业务执行之后,分配临时用户，让浏览器保存
     * @param request
     * @param response
     * @param handler
     * @param modelAndView
     * @throws Exception
     */
    @Override
    public void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler, ModelAndView modelAndView) throws Exception {
        UserInfoTo userInfoTo = threadLocal.get();
        if (!userInfoTo.isTempUser()) {
            Cookie cookie = new Cookie(CartConstant.TEMP_USER_COOKIE_NAME,userInfoTo.getUserKey());
            cookie.setDomain("gulimall.com");
            cookie.setMaxAge(CartConstant.TEMP_USER_COOKIE_TIMEOUT);
            //cookie过期时间
            response.addCookie(cookie);  //向浏览器添加cookie
        }
    }
}
